package main

import "fmt"

type Director int

const (
    East Director = iota
    South
    West
    North
)

func (d Director) String() string {
    return [...]string{"东", "南", "西", "北"}[d]
}

func main() {
    fmt.Println(East)
    fmt.Println(South)
    fmt.Println(West)
    fmt.Println(North)
}
